OK, I’m not the brightest guy in the world, but one would think that at this stage in my life, figuring out how to open a goddamned door would be something I would have mastered. You see the handle, you turn it - jiggling it if need be - and you push or pull, depending on the nature of the door itself. Not too tough. Yet there I was, on Thanksgiving evening, at my parents’ home in Mattoon, Illinois, staring at our patio door, perplexed. Rather than the traditional round, turn-left/turn-right knob of my youth, there was this slender rod jutting out of the side of the door.

I didn’t know whether to lift it, turn it, push it, pull it or just command it: “Open thyself.” This was the home I had lived in since age 4, the house my father had built in our rural community, a place where the Leitch family has resided for generations, and here I was, not for the first time, having no idea how to get out.

I approached my mother.

“Mom, what’s with this door?”

She sighed, put aside her knitting - my mom knits now - and with a heavy look of resignation, walked over to me.

“We had all the handles in the house switched. It’s just a lever you pull down on. We switched them because of our arthritis. It hurts to open the regular kinds of doors.”

She then opened the door for me and chastised me for needing a cigarette, the only reason I wanted to go out in the first place.

Yep, I realized it more than ever when I went home for Thanksgiving: My parents are getting old.

Those people who had no choice but stay up until 3 a.m. waiting for me to get home now can’t make it a minute past 10. They’ve gone from a 12-pack during a baseball game to two beers and they’re out. My dad used to throw me mile-high pop-ups to help me practice for baseball; he now groans when he reaches across the table for the salt.

My parents are empty-nesters, old folks. So what does that make me?

My sister left for college more than a year ago, and ever since, I suspect my parents have been wondering what the heck to do with themselves. This is especially true because my sister was one of those high-maintenance kids, always rebelling and getting in trouble. She took so much of my parents’ energy and time that when she left - and it appeared she’d be just fine after all - my parents probably felt like they’d been left in a vacuum.

They have found new hobbies. My mother, a nurse and like all moms, a saint, had a spiritual awakening and decided to join the Catholic Church. She’s now so Catholic that I fear some of the life-long Catholics in her church get tired of her being so darned do-goody all the time.

I love that my mom has become Catholic; even though it’s not something I’m particularly interested in myself, she’s happier and more at peace. She has something more worthwhile to spend her money on than porcelain cat figurines.

True, she’s now pro-life, against gay marriage and seriously considering voting for Orrin Hatch, but you take the good with the bad, I guess.

Dad, on the other hand, has always been Mr. Fix-It. For years, his reputation as the Bob Vila of the extended family was tainted by his artsy son, who never could figure out the difference between a Phillips screwdriver and a ball peen hammer.

But with him out of the way, Dad blossomed. He completely rebuilt my grandmother’s home, helped my uncle build a new house and repainted the old 1967 Camaro that he and I - OK, mostly he - restored. He stayed busy all the time, holding off age for quite a while and staying useful to anyone who might need his help.

Time, however, is catching up with my parents, and me. Dad needs glasses to read the newspaper these days, and you have to repeat everything four or five times until he can hear what you said. No longer does he visit pals at the local bar, where he was once so familiar that the bartender knew my voice when Mom told me to call Dad home.

My parents never even leave the house anymore.

That’s all about to change, though. My parents, going through what I’m sure is probably their eighth midlife crisis, have decided to build a new house.

My lovely home - my sacred room, the only homebase I’ve ever known - is about to be sold to some family I don’t know. I remember being 4 years old and sitting next to my dad, him hammering something and me watching the miniature black-and-white TV he set up for me, while Dad built the house his family would live in for 20 years.

That house is as much a part of me as my left arm. And now they’re selling it.

Why? Not to move to Florida; my parents aren’t that old. No, my dad is building a new house, a full 50 feet from our old one.

My parents, in the wisdom of people who are ready to take the next step in their lives, are building a house for the sake of building a house. Gone will be the house for raising children; in its place will be a house for two - with a large basement and a big garage for whatever it is Dad does out there. They will, however, have a guestroom for - gasp- “the grandchildren.”

This is a house just for my parents. This is my father’s last big project, his crowning achievement, a house built at age 50. This is my parents’ nursing home, the place where they sit and grow old (older?) together. This will likely be the house my parents die in.

It would sound more romantic if, well, they weren’t deserting the home their kids grew up in. I leave for New York in a month, and when I come home next, there will be someone new living in my old house, my old room. (Maybe it’ll be a 15-year-old kid I can tell where all the Playboys are stashed.) When I talk about going home, I’ll be talking about my apartment, not Mattoon anymore.

I wonder how far it will go. Will my parents find bridge partners? Will they start playing bingo? Will they look at friends’ pictures of their grandkids and have to sheepishly explain, well, Will’s a writer in New York, and you know how they are.

I think what saddens me most about this whole thing is that my parents, after 24 years of dealing with having kids, are moving on. I’m out of the way now; it’s time to work on their own lives. That’s what 50-year-olds decide to do when the kids are gone, I guess; they decide to get old. I shudder to think how much older my parents will look in the future. They look much younger than 50 now, but that’ll change, and I’ll notice it each time I come to visit, on visits that will probably come less and less often as the years go by now that I’m going to New York. I hope they won’t forget about me, the way they’ll forget where their glasses are when they’re sitting on top of their heads.

Thanksgiving night, we went to visit cousin Denny at his parents’ house in Mattoon. Uncle Ron and Aunt Judy were always the lively ones when I was a kid, the ones who let me stay up late when I spent the night, the ones who made my parents look damned lame in comparison. They weren’t parents, they were buddies, and we stayed up late and joked and played Nintendo together.

Mom and I walked up to Uncle Ron and Aunt Judy’s door; I couldn’t figure out how to get the goddamned thing open.